"I didn't know how I would feel (after she died), but I feel her everywhere I go," he explained. "I feel the choices that she made, I feel the strength that she had and the love that she has for me and our family."

"As amazing as our love story is and has become over the years, all great stories have a beginning and ours was tough, like everyone else's," he told TODAY's Matt Lauer. "We were different. She didn't want to be a mother, and I had two little girls that I was raising on my own. .. And I didn't want to be married to someone who wanted to be a singer."

So they turned to faith, rather than reason.

Nathan Congleton / TODAY

"Those were pretty big obstacles, but we believed we were meant to be together," Rory recalled. At the time he thought, "'Ok, I'm not going to get my way, she's not going to get her way.'"

"In the end, God had a different plan," he said. "Not only did we get to have an amazing marriage, but he turned it into a music career together, and a story that's been shared with lots of other folks."

Jason Merritt / Getty Images

Joey + Rory perform on stage during the 2009 CMT Music Awards at the Sommet Center on June 16, 2009, in Nashville, Tennessee.

That's the lesson that Rory takes from their love story — and the one he shares in his new book, "This Life I Live" — that faith transforms.

"Sometimes faith can change everything," he insisted. "Just faith in something greater than what you lived before. It doesn't matter where you came from. I'm an unlikely person to be part of an amazing love story. I hope that's an encouragement to others."

Rory Feek on Joey's cancer battle, new film: 'She was an extraordinary woman'

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Rory Feek on Joey's cancer battle, new film: 'She was an extraordinary woman'

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Now, despite his loss, Rory is looking ahead. Not to a life without his wife, but to one with her — in a different way.

"I see an amazing journey that God has in store for all of us, for my children and I, and Joey's going to be part of it," he said. "He's still going to be giving us a great story. It's going to be different."